The specific objectives of the Neurohistology, Morphometry, and Data Processing Core are to provide neuroanatomic, neuropathologic, and morpnometric analysis for all appropriate postnatal brains generated by each of the Research Components of the Program Project. As the central warehouse of all postnatal neuroanatomic material, this Core is a natural repository for all behavioral, anatomic, and morphometric data from each of the Projects, as well as an ideal resource for statistical support for the Program Project as a whole. The Core will be involved in the steps leading to publication of all results that contain neuroanatomic and pathologic findings, and for this purpose it will provide support to the several research Projects in the preparation of illustrations of postnatal neuroanatomic and pathologic materials. Some of the additional activities of this Core, but which are not part of the current application, include the processing of human brains of individuals with learning disorders and control specimens, which are used to describe neuroanatomic findings and generate neuroanatomic hypotheses that can be tested in animal models such as those in the present Program Project.